# EXERCISE 16.1

**QUESTION 1**

Compute :

(i)

Sol :

= 870

(ii)

Sol :

= 100

(iii) L.C.M.

Sol :

Therefore, and can be rewritten as:

LCM of and

**QUESTION 2**

Prove that

Sol :

Hence , proved

**QUESTION 3**

Find in each of the following:

(i)

Sol :

(ii)

Sol :

(iii)

Sol :

**QUESTION 4**

Convert the following products into factorials:

(i)

Sol :

(ii)

Sol :

(iii)

Sol :

(iv)

Sol :

**QUESTION 5**

Which of the following are true :

(i)

Sol :

=120

= 8

Since

Thus , (i) is false

(ii)

Sol :

= 720

= 12

Thus , (ii) is false

**QUESTION 6**

Prove that:

Sol :

Hence proved

**QUESTION 7**

If find

Sol :

**QUESTION 8**

If find

Sol :

On comparing, we get:

**QUESTION 9**

If find

Sol :

**QUESTION 10**

If and are in the ratio find

Sol :

**QUESTION 11**

Prove that:

(i)

Sol :

(ii)

Sol :

L H S

Hence proved

**QUESTION 12**

Prove that:

Sol :

Hence proved